Frost dates for 97834Halfway, OR
The average last spring frost in Halfway is May 15 and the average first fall frost is September 24, giving a typical growing season of about 130 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 15
- Average first fall frost
- Sep 24
- Growing season
- 130 days
Safer after Jun 2 (1-in-10 risk)
Possible by Sep 9 (1-in-10 risk)
Last frost typically in 194 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | May 18 · Jun 5 · Jun 24 | Aug 28 · Sep 12 · Sep 26 | 96 days | 100% |
| Frost / freeze (32°F) | May 2 · May 15 · Jun 2 | Sep 9 · Sep 24 · Oct 6 | 130 days | 100% |
| Hard freeze (28°F) | Apr 18 · May 2 · May 16 | Sep 22 · Oct 5 · Oct 21 | 155 days | 100% |
Planting calendar for Halfway
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Apr 14 – Jun 20 |
| Tomatoes | Transplant outdoors | May 31 – Jun 4 |
| Peppers | Start seeds indoors | Apr 14 – May 15 |
| Peppers | Transplant outdoors | Jun 14 – Jul 15 |
| Eggplant | Start seeds indoors | May 1 – May 30 |
| Eggplant | Transplant outdoors | Jun 14 – Jul 15 |
| Cucumbers | Sow outdoors | Jun 14 – Jun 14 |
| Summer squash | Sow outdoors | May 31 – Jul 15 |
| Winter squash & pumpkins | Sow outdoors | Jun 14 – Jul 15 |
| Snap beans | Sow outdoors | May 31 – Jul 7 |
| Sweet corn | Sow outdoors | May 31 – Jun 4 |
| Watermelon & cantaloupe | Sow outdoors | Jun 14 – Jul 15 |
| Okra | Sow outdoors | Jun 7 – Jun 30 |
| Peas | Sow outdoors (spring) | Apr 14 – May 30 |
| Potatoes | Plant outdoors (spring) | Apr 14 – Jun 14 |
| Onions | Start seeds indoors (spring) | Mar 3 – Mar 30 |
| Onions | Transplant outdoors (spring) | May 1 – May 30 |
| Broccoli | Start seeds indoors (spring) | Mar 27 – Apr 30 |
| Broccoli | Transplant outdoors (spring) | May 1 – May 30 |
| Broccoli | Start seeds indoors (fall) | May 25 – Jun 4 |
| Broccoli | Transplant outdoors (fall) | Jun 24 – Jul 5 |
| Cabbage | Start seeds indoors (spring) | Mar 17 – Apr 14 |
| Cabbage | Transplant outdoors (spring) | Apr 14 – May 15 |
| Cabbage | Start seeds indoors (fall) | May 15 – Jun 14 |
| Cabbage | Transplant outdoors (fall) | Jun 14 – Jul 15 |
| Leaf lettuce | Sow outdoors (spring) | Apr 14 – Jun 30 |
| Leaf lettuce | Sow outdoors (fall) | Jun 14 – Jul 31 |
| Spinach | Sow outdoors (spring) | Apr 7 – May 21 |
| Spinach | Sow outdoors (fall) | Jul 1 – Aug 5 |
| Radishes | Sow outdoors (spring) | Apr 14 – Jun 4 |
| Radishes | Sow outdoors (fall) | Jun 14 – Aug 15 |
| Kale | Sow outdoors (spring) | May 1 – May 21 |
| Kale | Sow outdoors (fall) | Jun 7 – Jul 15 |
| Carrots | Sow outdoors (spring) | May 15 – Jun 30 |
| Carrots | Sow outdoors (fall) | May 15 – Jun 30 |
| Garlic | Plant outdoors (fall) | Sep 14 – Oct 15 |
Where these dates come from
ZIP code 97834 is matched to the NOAA station Halfway, OR, 2 km away, at 2,653 ft elevation (80 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Halfway, OR (used) | 2,653 ft | May 15 | Sep 24 |
| Richland, OR | 2,215 ft | May 10 | Oct 1 |
| Brownlee Dam, ID | 1,844 ft | Apr 2 | Nov 5 |
| Cambridge, ID | 2,650 ft | May 15 | Sep 27 |
Frost dates near Halfway
- Richland, OR 97870 · last May 15, first Sep 24
- Oxbow, OR 97840 · last Apr 2, first Nov 5
- Cambridge, ID 83610 · last May 15, first Sep 27
- Durkee, OR 97905 · last May 25, first Sep 15
- Joseph, OR 97846 · last May 24, first Oct 1
- Council, ID 83612 · last May 10, first Oct 2
- Baker City, OR 97814 · last May 25, first Sep 15
- Huntington, OR 97907 · last Apr 23, first Oct 13
Frequently asked questions
- When is the last frost in Halfway, OR?
- For ZIP code 97834, the average last spring frost (32°F) is May 15, based on NOAA 1991-2020 climate normals for the Halfway, OR weather station. There is a 1-in-10 chance of a frost after June 2.
- When is the first frost in Halfway, OR?
- The average first fall frost (32°F) is September 24. There is a 1-in-10 chance of frost by September 9, so tender plants are at risk from that point on.
- How long is the growing season in 97834?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 130 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.